﻿var radius = 90;
var d = 200;
var dtr = Math.PI / 180;
var mcList = [];
var lasta = 1;
var lastb = 1;
var distr = true;
var tspeed = 11;
var size = 200;
var mouseX = 0;
var mouseY = 10;
var howElliptical = 1;
var aA = null;
var oDiv = null;
window.onload = function() {
	var i = 0;
	var oTag = null;
	oDiv = document.getElementById('tagscloud');
	if (oDiv) {
		aA = oDiv.getElementsByTagName('a');
		for (i = 0; i < aA.length; i++) {
			oTag = {};
			aA[i].onmouseover = (function(obj) {
				return function() {
					obj.on = true;
					this.style.zIndex = 9999;
					this.style.color = '#fff';
					this.style.padding = '5px 5px';
					this.style.filter = "alpha(opacity=100)";
					this.style.opacity = 1;
				}
			})(oTag)
			aA[i].onmouseout = (function(obj) {
				return function() {
					obj.on = false;
					this.style.zIndex = obj.zIndex;
					this.style.color = '#fff';
					this.style.padding = '5px';
					this.style.filter = "alpha(opacity=" + 100 * obj.alpha + ")";
					this.style.opacity = obj.alpha;
					this.style.zIndex = obj.zIndex;
				}
			})(oTag)
			oTag.offsetWidth = aA[i].offsetWidth;
			oTag.offsetHeight = aA[i].offsetHeight;
			mcList.push(oTag);
		}
		sineCosine(0, 0, 0);
		positionAll();
		(function() {
			update();
			setTimeout(arguments.callee, 40);
		})();
	}
};

function update() {
	var a, b, c = 0;
	a = (Math.min(Math.max(-mouseY, -size), size) / radius) * tspeed;
	b = (-Math.min(Math.max(-mouseX, -size), size) / radius) * tspeed;
	lasta = a;
	lastb = b;
	if (Math.abs(a) <= 0.01 && Math.abs(b) <= 0.01) {
		return;
	}
	sineCosine(a, b, c);
	for (var i = 0; i < mcList.length; i++) {
		if (mcList[i].on) {
			continue;
		}
		var rx1 = mcList[i].cx;
		var ry1 = mcList[i].cy * ca + mcList[i].cz * (-sa);
		var rz1 = mcList[i].cy * sa + mcList[i].cz * ca;

		var rx2 = rx1 * cb + rz1 * sb;
		var ry2 = ry1;
		var rz2 = rx1 * (-sb) + rz1 * cb;

		var rx3 = rx2 * cc + ry2 * (-sc);
		var ry3 = rx2 * sc + ry2 * cc;
		var rz3 = rz2;

		mcList[i].cx = rx3;
		mcList[i].cy = ry3;
		mcList[i].cz = rz3;

		per = d / (d + rz3);

		mcList[i].x = (howElliptical * rx3 * per) - (howElliptical * 2);
		mcList[i].y = ry3 * per;
		mcList[i].scale = per;
		var alpha = per;
		alpha = (alpha - 0.6) * (10 / 6);
		mcList[i].alpha = alpha * alpha * alpha - 0.2;
		mcList[i].zIndex = Math.ceil(100 - Math.floor(mcList[i].cz));
	}
	doPosition();
}

function positionAll() {
	var phi = 0;
	var theta = 0;
	var max = mcList.length;
	for (var i = 0; i < max; i++) {
		if (distr) {
			phi = Math.acos(-1 + (2 * (i + 1) - 1) / max);
			theta = Math.sqrt(max * Math.PI) * phi;
		} else {
			phi = Math.random() * (Math.PI);
			theta = Math.random() * (2 * Math.PI);
		}
		//坐标变换
		mcList[i].cx = radius * Math.cos(theta) * Math.sin(phi);
		mcList[i].cy = radius * Math.sin(theta) * Math.sin(phi);
		mcList[i].cz = radius * Math.cos(phi);

		aA[i].style.left = mcList[i].cx + oDiv.offsetWidth / 2 - mcList[i].offsetWidth / 2 + 'px';
		aA[i].style.top = mcList[i].cy + oDiv.offsetHeight / 2 - mcList[i].offsetHeight / 2 + 'px';
	}
}

function doPosition() {
	var l = oDiv.offsetWidth / 2;
	var t = oDiv.offsetHeight / 2;
	for (var i = 0; i < mcList.length; i++) {
		if (mcList[i].on) {
			continue;
		}
		var aAs = aA[i].style;
		if (mcList[i].alpha > 0.1) {
			if (aAs.display != '') {
				aAs.display = '';
			}
		} else {
			if (aAs.display != 'none') {
				aAs.display = 'none';
			}
			continue;
		}
		aAs.left = mcList[i].cx + l - mcList[i].offsetWidth / 2 + 'px';
		aAs.top = mcList[i].cy + t - mcList[i].offsetHeight / 2 + 'px';
		//aAs.fontSize=Math.ceil(12*mcList[i].scale/2)+8+'px';
		//aAs.filter="progid:DXImageTransform.Microsoft.Alpha(opacity="+100*mcList[i].alpha+")";
		aAs.filter = "alpha(opacity=" + 100 * mcList[i].alpha + ")";
		aAs.zIndex = mcList[i].zIndex;
		aAs.opacity = mcList[i].alpha;
	}
}

function sineCosine(a, b, c) {
	sa = Math.sin(a * dtr);
	ca = Math.cos(a * dtr);
	sb = Math.sin(b * dtr);
	cb = Math.cos(b * dtr);
	sc = Math.sin(c * dtr);
	cc = Math.cos(c * dtr);
}